A new trend I’m seeing in attic mold removal is what I call the “hide-and-hope method.” As in hide the problem and hope the buyer’s home inspector doesn’t find it. I have been installing attic ventilation systems and removing mold from attics for more than 20 years and I am also a licensed home inspector. I can attest that whatever method of mold removal is used, there will always be a telltale sign that remediation was performed.

If a seller does not list the fact that mold remediation was performed on the property and the home inspector finds it, how will that make anyone in the transaction feel? As a real estate agent, you now have to go back to the buyer and tell them that the seller tried to pull a fast one. As the homeowner selling the property, you will always live with the knowledge that you passed along a potential problem to someone else without making him or her aware of it. The buyer now wonders that if the mold issue was not disclosed and an attempt to cover it up was made, what else about the property was not disclosed or covered up. The whole deal is then tainted and trust is broken. The hide-and-hope method is a huge chance to take, creates a red flag for the entire transaction, and I do not recommend it. The home inspection will actually go much better if any known problems and what may or not have been done to fix those problems are disclosed. Honesty is the best policy for all involved.

When Quigley Attic Mold performs attic mold remediation, we list what the original cause of the problem was (for example, bathroom fans venting into the attic, lack of proper ventilation, etc). We then fix the problems that led to the mold growth, and remove the mold. To insure that the mold has been completely removed, we finish each job with an antimicrobial sealant. The sealant is white and contains properties that inhibit new mold growth and makes it extremely easy to see that all mold and any residual stains have been removed. We then provide a transferrable warranty to the homeowner to pass along to the buyer. When the home inspector shows up, he or she can now put in the report that there was a problem caused by such-and-such that had resulted in mold growth. He or she can now note that the problem was addressed, the mold completely removed and the transferable warranty is in place. Instead of employing the hide-and-hope method, remember that the solve-and-share system works better for all involved in any real estate transaction.

The common problem: A client has excess humidity in the attic in the winter and excess heat in the summer. The client applies the logic that installing a fan will cool down the attic and remove the water vapor. This is an erroneous solution put forth by home improvement stores, as well as contractors and home inspectors who mean well but are not certified specialists.

So the question frequently posed to me by a homeowner is, “Should I, or should I not, install a gable vent exhaust fan in my attic?”

The answer is, almost never. In certain circumstances, where no other form of ventilation is feasible, I might consider it, but only after a complete evaluation of the home. The negative air pressure created by the fan can actually make the attic and house warmer, rather than cooler. The fan can draw warmer exhausting air down from the ridge upsetting natural air flow and causing the attic to get warmer. The fan can also pull air conditioned (cooler) air up from the living space causing the house to get warmer while removing the cooler air to the exterior. This causes the air conditioning system to run longer using more electricity, while the gable fan is running using, yup, even more electricity. How efficient or “green” is that? Not very.

Every home is different and requires an evaluation of the whole of its systems, rather than the parts. When your home was built and brand new it had a balanced system. Well-meaning homeowners may inadvertently upset that delicate balance in a number of ways. Adding more insulation, replacing the windows or upgrading the heating system can significantly alter the way a home operates. Unfortunately, the result of these good intentions is usually mold growth in the attic.

When attic mold is involved in the sale of a home, I am frequently asked, “what is the one thing we need to do to correct the attic mold problem”? Unfortunately, it is usually never one thing causing the mold, but instead is a combination of multiple contributors.

Usually, excess moisture enters the attic through the ceiling, utility chases, electrical fixtures, missing or improperly installed insulation, and the attic entry way. This warm moist air is condensing on the colder roof structures during the fall, winter, and spring months. Without proper ventilation, excess moisture cannot be carried away.

Mold in the attic is typically caused by the intrusion of warm moist air due to elevated humidity in the living space from:

A client bought a house two years ago with no mold growth in the attic space. He installed replacement windows and added insulation to the attic and basement. The house was warmer but it also retained more water vapor. Since the client did not add ventilation to the attic space to remove the excess water vapor that was created when the house was tightened up, water droplets formed on the attic sheathing (plywood) and allowed the ever-present mold spores floating in the air to start growing. The client created his own mold problem.

I see this time and time again and it is almost always as a result of weatherization programs. The golden rule is, if you insulate, you must ventilate.

Client: “My wife says she cannot breathe in the bedroom, so she will not sleep with me. I need you to come to my house and determine if there is a mold problem.”

Arriving to the rescue, I discovered that plastic had been taped over all of the upstairs bedroom windows, effectively sealing the room off from any fresh air supply. When I was young, everyone knew enough not to put a plastic bag over your head because you would suffocate. These days, common sense seems to fly right out the window.

Me: “Take the plastic off the windows and open them up for some fresh air.”

Client: “I’m trying to reduce my heating bill.”

Me:” At some point you have to determine if the course of action you are taking is logical. It’s great if you can heat your energy efficient and tightly sealed home using only a match. It is not so great if the air quality in your home is so poor that everyone in the house becomes sick.”

My recommendation for healthy air quality is this:

In the summer, use some type of air conditioning system to remove high levels of humidity from the house. Open the windows when the humidity is low to let some fresh air in. Make sure you open the windows in the fall to let trapped moisture out of your home. Trapped moisture will show up on the insides of your windows as warm moist air attaches to the cold glass.

A Helpful Hint: Lower the top sash on a double hung window and raise the bottom sash. This will let stale air out through the top and bring fresh air in through the bottom.

In the winter the mold spores outside are usually covered with a layer of snow. This will be your freshest, cleanest air. Every once in a while, during the winter months, open the windows and let some fresh air in. Your wife will thank you for it.

When your home was new, all the systems were in balance. We will call each original system of the home “X”. All changes will be called “Y”. The heating system, windows, insulation, ventilation system, septic system, yard grading etc. all matched in “X”. Now we will see how a perfectly matched home is systematically destroyed by well intentioned homeowners.

This series is intended to help home owners understand how seemingly small changes can affect the entire home.

Part One: House “X” was new and occupied by the original homeowners for 10 years. During the home inspection for the new buyers mold was discovered in the attic.

What changed? This house was built with a ventilated drip edge. This “hicks” style vent was designed to replace standard soffit vents. The caveat with this type of system is that you cannot use gutters with it.

The problem: The overhang on the house was so narrow that when water dripped off the edge of the roof, it splashed on the ground and back up on to the siding causing rot. That could have been avoided if the overhang was larger or the foundation was taller. Not aware of the no gutters with hicks vent rule, the homeowner attempting to solve the problem installed gutters on the house. Water was inevitably trapped in the gutter by debris, leaves, branches, and poor slope etc. As the sun baked the gutters, water evaporated and was drawn into the “vents” over the gutter. These are after all, intake vents which are half of a balanced attic ventilation system. The top half of this system is called the ridge vent.

The result: Excess water vapor in the attic activated floating dormant mold spores. The mold spores attached to the damp attic roof sheathing and started to form colonies. Mold remediation will have to be completed and the ventilation system will have to be changed to allow for the new gutter system.

The solution: Remove the “hicks” vents and install under the gutter soffit vents. Remember to match the intake with the exhaust for a balanced ventilation system. For example: If nine square inches per linear foot is installed at each soffit, then a total of eighteen inches per linear foot will need to be installed at the ridge.

In this scenario, the house was not designed to have gutters. Adding gutters changed “X” to “Y”. Adding the soffit vents and removing the over the gutter “hicks” vents brings the house back to “X”.

I was called to investigate a mold problem in an attic. The client had had a home inspection and the recommendation was to have the suspected microbial activity in the attic space further evaluated. I use that same wording on my reports. I asked of there were any pictures from the inspection he could forward to me . Usually the answer is no, the inspector did not take pictures. I take an average of 250 picture when I do an inspection. I digress. This inspector did take pictures and the client sent them to me.

The exterior inspection clearly showed a decent ridge vent and vented soffit panels. The interior showed soffit vent chutes. The inspector did the right thing in requesting a further evaluation. The inspector cannot disturb insulation while performing the home inspection. He couldn’t see that air sealing was not completed under the insulation. That’s not his job, it’s mine. Because there was no floor in the attic, the inspector could not enter to perform a complete inspection. Again, not his job, it’s mine. I brought some temporary flooring with me and crawled into the attic space. With the lights off I should have been able to see daylight at the soffit area. I thought this was another case of the siding contractor installing vents over solid wood soffits.

What I found was unusual. The siding contractor did cut the opening for the soffit. The soffit panels were covered with debris restricting air flow into the attic. We simply removed the soffit panels, vacuumed the panels and openings and re-installed the panels.

While measuring the attic for mold remediation, I noticed another problem. The insulation contractor used blown in cellulose insulation which is fine. However, he also managed to clog the ridge vent with insulation restricting exhaust at the ridge. We simply vacuumed that too. Proper ventilation was achieved with a vacuum cleaner. Air sealing was achieved with four cans of spray foam insulation. We remediated the attic , the deal went through and everyone was happy.

A typical call goes something like this. Good morning mold person. I had a home inspection and they found mold in my attic and recommended removing the mold and improving the attic ventilation system. I had a contractor in to install ridge venting now I need the mold removed.

In my head I am thinking ” mold removal before ventilation” not the other way around. I say it over and over again. The process of mold removal and the application of sealant can clog new ridge vents. I arrived at the house and this is what I found. The contractor drilled a 3/4″ hole through the ridge every 16″, misinterpreting the code of a 3/4″ minimum continuous cut. On top of that he installed a rolled ridge vent that was collapsed and performing no function.

The 3/4″ cut is too small for the amounts of insulation we have in our homes. My recommendation is to double that to 1 1/2″. Also, I have to remove the new ridge vent and caps, properly cut open the ridge and install a new performing ridge vent and caps.

In the image I have here you can see that the ridge cut should be equal to the vented opening of the ridge vent. The blue mesh filter should span side to side.

The other low bid, great deal contractor disappeared after the job and the homeowner had to pay the bill for the new work. I am not completely blaming the contractor. The homeowner is probably equally at fault. I bet there was at least one bid, probably the highest, who told the homeowner exactly what needed to be done.

Also remember that the general contractor, roofing contractor or home improvement contractor all are not ventilation or mold experts. Hire only qualified and insured (liability and workman’s comp insurance) certified mold remediation and ventilation contractors.

I was called by a customer about a suspected mold problem in his attic. He then told me he thought there may be a roof leak because it sounded like water was dripping. I went out to investigate. Sure enough it was raining in his attic. The roofing nails were collecting water vapor and dripping back down on to the insulation and air handler. The plywood roof sheathing was so wet it looked like a sheet of water was cascading down the surface. The gable end was completely covered with wet slimy black mold.

So I said, “how long has this been going on?”. He said “just this winter”. My next question was, “what conditions have changed since last year?”. He said “we got a new roof a few months ago”.

This is what happened. The roofer installed a rolled ridge vent that completely collapsed upon installation of the ridge caps. Water vapor could not escape the attic. The solution was a new collapse resistant ridge vent. Problem solved. I am sure that at least one roofing contractor wanted to install the correct vent, which cost more, and was outbid and didn’t get the job.

The cost to the client. He not only had to pay for a new ridge vent to be installed but also had to pay for the mold remediation of his attic. Did the first roofing contractor do him wrong on purpose? Probably not. The roofing contractor is not a ventilation specialist and probably didn’t know any better. In this case the roofing contractor had been using the same ridge vent for years without problems. The vent never worked but the problem of moisture retention did not present itself until the home was made more efficient. When the home was made more efficient the underperforming or improperly installed ridge vent was finally revealed.

With homes getting tighter and tighter as a result of energy conservation, more attention needs to given to indoor air quality and ventilation issues across the board.